My guess is that because Tomy presumably produced their own gears they began to produce "funkier" gears that would cost them less than using individual parts like the metal shaft required for that intermediate gear on the older mail car. That 24 tooth gear looks like it should work as long as you find a 2.5mm axle to put it on that will fit into the molding slots on the chassis. The 9 tooth gear looks like the same type I bought to repair the handful of Plarail related things that used the same gear (some of the later friction-drive Merry Go trains use them on the motor shaft). The 16 tooth gear looks like it should work too.
I usually cannibalize and cut down shafts from junked gearboxes/trains.
I believe this is the thread Super mentioned. I also have some notes about that gearbox here on my site.
I usually cannibalize and cut down shafts from junked gearboxes/trains.
I believe this is the thread Super mentioned. I also have some notes about that gearbox here on my site.
I have a website where I have been writing about and photographing many of the sets and pieces that I find interesting.
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